Our Research Lab
Device Sound Quality
A key benchmark for any new hearing device is a robust comparison of the new device to existing devices produced by the leading, well-established, market shareholders. Reasonable comparisons often include subjective measures based on use by human subjects. Because sound quality is a key metric for consumers, manufacturers, and hearing professionals, we evaluate the sound quality of various devices in a variety of natural auditory scenes using virtual audio and various measurement methods. Classic methods involve a single sound scene and ask the listener to rate various sound qualities on a 10-point rating scale. This method is tried and true but is limited to measurement of one device at a time since the ratings take several minutes to complete.
We have implemented a second method that involves “A/B” comparisons of multiple devices at the same time. Because of the time it takes to remove and replace devices on a human subject, we use a manikin known as the Klangspectrum Klangfinder to position up to three pairs of devices in the desired acoustic environment at once. We then route the sound recorded from the ear simulators built into the manikin to a human listener in another room who is listing via headphones to the sound environment that is being processed in real time by hearing aids. With this method, they can use a software interface to instantaneously switch the devices to which they are listening from one to another.
Left: Klangspectrum Klangfinder Acoustic Manikin with six ear simulators (3 on each side)
Right: Sample user interface for A/B sound quality comparisons
A third technique known as Multiple Stimuli with Hidden Reference and Anchor (MUSHRA). This project builds on a university-industry partnership between Bose and the Auditory & Speech Sciences Laboratory at USF that has been ongoing.